Elevated anti-inflammatory effects of eicosapentaenoic acid based self-aggregated glycol chitosan nanoparticles

The formation of nanoparticles from eicosapentaenoic acid (EPA) is crucial to improving EPA's bioavailability and pharmacological properties, and widening its use in biomedical fields. In this study, we report EPA-conjugated glycol chitosan (GC) that can self-aggregate into core-shell nanoparticles. The EPA-GC nanoparticles were internalized into the cytosol of RAW 264.7 cells by endocytosis, which results in effective delivery of EPA to the cells. There were no differences in the cell viability after the treatment with EPA-GC nanoparticles. In the anti-inflammatory studies, the EPA-GC nanoparticles significantly inhibited lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production and interleukin-1 beta (IL-1 beta) secretion in RAW 264.7 cells. The anti-inflammatory effects of the EPA-GC nanoparticles were far better than those seen for EPA only. Given their excellent bio-physicochemical properties, it is expected that EPA-GC nanoparticles may have a potential for widening the use of EPA in biomedical fields and, in particular, the treatment of inflammatory diseases.